Weapon trainer using IR radiation emitted from target

ABSTRACT

A marksmanship training system has been developed which depends upon the  mal levels of infrared radiation emitted from warm-blooded animals, such as humans. An infrared detector is mounted upon a simulated rifle or unloaded real rifle, or other weapon. This detector is mounted with IR lenses in such a way that a positive indication is given when the rifle is pointed at a suitable infrared emitting animal target. A second detector indicates when the trigger of the weapon is pulled. If a trigger pull is detected at a time when an animal infrared signal is present, the system generates an electronic pulse indicating that a target hit has occurred. This pulse may be used to drive a visible or audible signaling device to inform the user of success.

BACKGROUND OF THE INVENTION

Numerous training devices have been developed which allow marksman to betrained without the use of expensive and dangerous live ammunition.However, most such devices require that the training take place underunrealistic conditions, such as when special targets containing lightsources are used. Furthermore, even live fire training takes place underartificial conditions, compared to those conditions found in actualwarfare, since the fire must be confined to target ranges and confinedin narrow paths for safety reasons.

Accordingly, it is an object of this invention to provide a marksmanshiptraining device which can be used under fully realistic conditionsagainst the actual types of targets that would be encountered inwarfare.

Another object of this invention is to provide a lightweight andinexpensive training system that does not require expensive dedicatedbuildings or land to enclose target ranges.

To achieve these and other objects, a system has been developed whichdepends upon the normal levels of infrared radiation emitted from warmblooded animals, such as humans. A pyroelectric long wave lengthinfrared detector is mounted upon a simulated rifle or unloaded realrifle, or other weapon. This detector is mounted on the end of a rifleand boresighted with the rifles sights in such a way that a positiveindication is given when the rifle is pointed at a suitable infraredemitting animal target. A second switch indicates when the trigger ofthe weapon is pulled. If a trigger pull is detected at a time when ananimal infrared signal is present, the system generates an electronicpulse indicating that a target hit has occurred. This pulse may be usedto drive a visible or audible signaling device to inform the user ofsuccess.

SUMMARY OF THE INVENTION

A marksmanship training system comprising an infrared detector mountedupon a simulated rifle or unloaded real rifle, or other weapon. Thisdetector is mounted with lenses in such a way that a positive indicationis given when the rifle is pointed at a suitable infrared emittinganimal target. A second detector indicates when the trigger of theweapon is pulled. If a trigger pull is detected at a time when an animalinfrared signal is present, the system generates an electronic pulseindicating that a target hit has occurred. This pulse may be use todrive a visible or audible signaling device to inform the user ofsuccess.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of the training system described herein.

FIG. 2 is the electrical schematic of an actual embodiment of thesystem.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 is a schematic of the weapon trainer system and IR lens. Lens 1,is used to focus infrared energy being emitted from a human target ontoa pyro electric detector 2, which detector provides an alternatingcurrent output signal from an internal chopper.

A man at 98 degrees F. radiates longwave infrared energy of wavelengthsin the 10 to 14 micron region. Thus, lens 1 must be chosen so that itcan operate at these long wavelengths and properly focus energy onto thedetector. A lense with a narrow field of view combined with a detectorsensitive to 10 to 14 micron wavelengths will indicate the presence of aman-target only when the lense is pointed at the target. Preferably, thelens and detector are mounted upon a weapon in a manner such that thetargets identified by the lens and detector are the same as those thatwould be identified by the normal sight of the weapon.

The output of detector 2 is processed by low pass filter 3. This filtereliminates high frequency noise generated in the environment and in thedetector itself. This noise would otherwise cause false indications ofsuccessful target hits.

The output of the filter 3 is amplified by high gain amplifier 4. Aninverted output is provided by inverting buffer 5.

In order to screen out false signals caused by detector ringing andother forms of noise, output from the detector/amplifier system isblocked for a short period after target acquisition by the output oftimer 7. This blocking is accomplished by output disabling circuit 8.

The RESET output from amplifier 4 and SET output from inverting buffer 5is passed through amplifiers 9 and 10 to the set and reset inputs offlip-flop 11.

If a valid target is engaged at a given point in time, the flip-flopoutput to AND gate 12 will be true. If target engagement is lost, theRESET line will cause the flip-flop to output a false signal to AND gate12.

Trigger switch 13 is normally open, and thus normally provides a falsesignal to the other input of AND gate 12. When the trigger is pulled,the switch opens and a true signal is applied to the AND gate input. Ifthe other AND input is also true at that moment, the output of AND gate12 will also indicate true. This means that the trigger was pulled at atime when the rifle was properly targeted.

FIG. 2 is a detailed schematic of a particular embodiment of theinvention. The chopper modulated output from the infrared detector ispassed through the low pass filter 3 and amplifier 4. The SET output ofamplfier 4 is passed through amplifier 9 to flip-flop 11. The output ofamplifier 4 is also inverted by inverting buffer 5. The RESET output ofbuffer 5 is passed through amplifier 10 to flip-flop 11.

The SET and RESET outputs of 4 and 5 are also sent to timer 7 via signaldetector 6. The timer output activates output disabling circuit 8. Thenet effect of the operations of 6, 7, and 8 is to disable the SET andRESET lines for a short period of time, in this case 250 mS, after anychange in the status of these lines is detected. If the change in statusdoes not last for at least 250 mS, the timer 7 will time out, and theoutput diable circuit 8 will also cease to function. Once this happens,the new status of the SET and RESET lines is available to flip-flop 11via amplifiers 9 and 10. The output of flip-flop 11 is correlated withthe pulling of trigger switch 13 by AND gate 12. If 13 is activated when11 is SET, 12 will output a pulse. This pulse can be used to activate asignal indicating that a target hit has occurred.

What we claim is:
 1. A weapons training device comprising:means fordetecting infrared radiation emitted by warm-blooded animals, includinghumans and heated targets; a simulated rifle; and means for detectingwhen the trigger of the said simulated rifle is pulled; wherein the saidmeans for detecting infrared radiation is mounted upon the rifle in sucha manner as to detect radiation emitted by said animals at such times asthe rifle is properly targeted at said animals.
 2. The training deviceof claim 1 wherein the said means for detecting infrared radiationcomprises a pyroelectric detector.
 3. The training device of claim 2wherein said means further comprise a low pass filter.
 4. The trainingdevice of claim 3 wherein said means for detecting when the trigger ispulled comprises a switch and a logic gate.
 5. The training device ofclaim 4 wherein said logic gate is an AND gate.
 6. The training deviceof claim 5 wherein the said means for detecting infrared radiationfurther comprise an inverting buffer, a timer, an output disablingcircuit, and a flip-flop wherein the output of said flip-flop isconnected to an input of said AND gate.